The invention relates generally to earth retaining walls. More particularly, the invention relates to a segmental retaining wall system comprising retaining means for attaching reinforcement members to the retaining wall.
Segmental retaining walls commonly are used for architectural and site development applications. Such walls are subjected to very high pressures exerted by lateral movements of the soil, temperature and shrinkage effects, and seismic loads. Therefore, the wall is often tied into the backfill soil, typically with tensile reinforcement members. Usually, elongated structures, commonly referred to as geogrids or reinforcement fabrics, are used to provide this reinforcement. Geogrids often are configured in a lattice arrangement and are constructed of a metal or plastic, while reinforcement fabrics are constructed of a woven or nonwoven polymer fibers or plastics. These reinforcement members typically extend rearwardly from the wall and into the soil to stabilize the soil against movement and thereby create a more stable soil mass which results in a more structurally secure retaining wall.
Although several different forms of reinforcement members have been developed, difficulties remain with respect to attachment of the members to retaining walls. In particular, the reinforcement members can shift out of position and be pulled away from the retaining wall due to movement of the soil. This difficulty especially can be problematic in areas of high seismic activity where a poorly secured gravity wall can topple. In response to this problem, several current retaining wall systems have been developed to retain geogrid reinforcement members. In one such system, rake shaped connector bars are positioned transversely in the center of the contact area between adjacent stacked blocks with the prongs of the connector bars extending through elongated apertures provided in the geogrid to retain it in place. Despite adequately holding the geogrid in position under normal conditions, this system of attachment provides a substantial drawback. Specifically, the geogrids of this system only extend along the back halves of the contact areas between the blocks. Although the geogrids are relatively thin, this partial insertion of the geogrids can cause the retaining wall to bow outwardly due to the aggregate thickness of the geogrids. As can be appreciated, this outward bowing can be substantial with tall retaining walls that require a multiplicity of geogrids. Aside from creating the impression of instability, this condition increases the likelihood of wall failure, particularly in response to seismic activity.
From the above, it can be appreciated that it would be desirable to have a mechanically stable wall system having secure retaining means for maintaining connection of reinforcement members to the retaining wall.
Briefly described, the present invention relates to a segmental retaining wall system. This system comprises a plurality of wall blocks. Each wall block comprise an interior face for forming an interior surface of a segmental retaining wall, an exterior face for forming an exterior surface of the segmental retaining wall, first and second sides that extend from said exterior face to said interior face, a top surface, and a bottom surface. In addition, the wall block includes retaining means for retaining a reinforcement member to the segmental retaining wall. In one arrangement, these retaining means comprises a channel that is defined by a front wall, a rear wall, and a channel bottom surface. This channel is provided in one of the faces and surfaces of the block, and preferably includes at least one inwardly extending shoulder.
The objects, features, and advantages of this invention will become apparent upon reading the following specification, when taken in conjunction with the accompanying drawings.